First, the purpose of rollback is to deal with bad edits.
I made an edit, you did not understand it, but nonetheless you reverted it with 'undo button' with a false claim of wrong markup, which it was not. I challenged you and restored it. Instead of you to explain your reasoning, you went ahead and just 'rollbacked' it with absolutely no reason just because you can. You cannot even explain what you're doing.
I will revert it. If you disagree with the edit, explain yourself and stop misusing rollback thinking just everything has to suit you.